An arbitrary pulse compatible high-speed camera synchronous trigger device

Abstract

The invention discloses an arbitrary pulse compatible high-speed camera synchronous trigger device, which is applied to a plasma photoelectric information acquisition system, and the system includes an excitation source, a plasma reactor, an arbitrary pulse compatible high-speed camera synchronous trigger device, a high-voltage probe, and a high-speed camera; the trigger device includes an electromagnetic interference minimization processing unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit. The excitation source releases a pulse excitation to act on the plasma reactor to break down the discharge; the high-voltage probe detects the pulse voltage signal of the discharge and transmits it to the compatible pulse trigger system; the compatible pulse trigger system performs differential anti-interference and hysteresis processing on the received discharge voltage signal to obtain a clean voltage signal; the processed discharge signal is transmitted to the high-speed camera to trigger the high-speed camera to shoot at the corresponding moment; the device is simple, highly active, highly accurate, highly anti-interference, and has good economy and practicability.

Description

Technical Field

[0001] The present invention relates to the field of plasma technology, and in particular to an arbitrary pulse compatible high-speed camera synchronous trigger device Background Art

[0002] In the information collection of the plasma discharge process, the time scale of different stages of the discharge process is in the nanosecond and microsecond level, so a high-speed camera is needed to record its spatiotemporal information. At the same time, high-frequency noise and electromagnetic interference will also be generated during the plasma generation process. At the same time, the excitation source itself is also an interference source. In order to solve the above-mentioned high-frequency noise interference problem, and to obtain undistorted high-speed camera synchronization trigger signals, and to be able to cope with different excitation sources to enable high-speed cameras to capture accurate photoelectric information, we need to make constructive engineering application solutions for photoelectric information collection in the field of plasma discharge.

[0003] At present, people have proposed and used a variety of methods to deal with high-dynamic image synchronous tracking and capture technology in different application fields: (1) Remote control type high-speed camera synchronous trigger technology; transmit the trigger signal to the receiver through Ethernet to complete the remote synchronous triggering of multiple high-speed cameras. This triggering method will integrate the trigger system into the camera or other communication components, and can only be applied to a single supporting device of the same model, with a single matching target and strong targeting. There are also certain limitations in terms of delay, and it is applied to application scenarios that do not have strict requirements on the dynamic time magnitude, such as emergency alarms of pumping wells. (2) Industrial manufacturing type high-speed camera synchronous trigger technology; additional trigger equipment is required, such as expensive synchronous trigger oscilloscopes, high-resolution signal generators, and difficult technical methods such as photomultiplier tubes or photon detection technology to obtain the acquisition trigger signal to trigger the camera shutter. Therefore, the high-dynamic image synchronous tracking and capture technology in the existing technology cannot meet the information collection of plasma discharge processes in multiple scenarios.

[0004] Study different electrodes under the stimulation of different excitation sources to obtain the complete process of electrode discharge from the beginning to the end. The discharge process of the electrode has strict control requirements on the time parameters due to the excitation parameters and performance of the excitation source, and a high-speed camera is needed to record the discharge process frame by frame. High-speed cameras can capture the instantaneous state or the entire process of high-speed physical phenomena, record a large amount of accurate time and space information, and provide a reliable basis for studying the generation mechanism and movement law of discharge plasma. Due to the various forms of excitation sources and the different excitation times, most of the trigger devices for high-speed cameras on the market can only be triggered due to one-to-one matching of the camera or the excitation source itself, so as to have a low delay and output accurate and good pulse waveform, so the technical parameters are relatively cumbersome. Therefore, a trigger method with high compatibility and simple method is required for different excitation sources to be able to identify and generate the corresponding required pulse trigger signal.

[0005] Therefore, the present invention can design an arbitrary pulse compatible high-speed camera synchronous trigger device in response to the needs in the field of plasma discharge technology and in combination with the advantages of high-speed cameras in collecting photoelectric physical information. Summary of the invention

[0006] 1. Technical problems to be solved:

[0007] In view of the above technical problems, the present invention provides an arbitrary pulse compatible high-speed camera synchronous trigger device; this device is applied to a highly compatible synchronous trigger method and an implementation device for various high-frequency excitation sources to stimulate plasma discharge and simultaneously trigger high-speed camera shooting in complex application scenarios such as high noise and high electromagnetic interference. The method is simple, highly active, highly accurate, highly anti-interference, and has good economy and practicability.

[0008] 2. Technical solution:

[0009] An arbitrary pulse compatible high-speed camera synchronous trigger device is applied to a plasma photoelectric information acquisition system, the system comprises an excitation source, a plasma reactor, an arbitrary pulse compatible high-speed camera synchronous trigger device, a high-voltage probe, and a high-speed camera, characterized in that: the arbitrary pulse compatible high-speed camera synchronous trigger device comprises an electromagnetic interference minimization processing unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit;

[0010] The excitation source is a high-frequency excitation source, which releases pulse excitation to the plasma reactor; the plasma discharge reactor breaks down and discharges under the action of the high-frequency excitation source; the high-voltage probe detects the pulse voltage signal of the plasma discharge reactor from the start to the end of the discharge, and transmits the detected signal to the compatible pulse trigger system; the compatible pulse trigger system performs differential anti-interference and hysteresis processing on the received discharge voltage signal to obtain a clean voltage signal; the processed discharge signal is transmitted to the high-speed camera to trigger the high-speed camera to shoot at the corresponding time;

[0011] The compatible trigger system includes an electromagnetic interference minimization processing unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit; the electromagnetic interference minimization processing unit generates a first signal after performing electromagnetic interference minimization processing on the discharge voltage signal of the plasma reactor detected by the high-voltage probe; the first signal is transmitted to the anti-interference hysteresis control unit and then generated as a second signal after positive feedback trigger reference hysteresis adjustment; the first signal and the second signal are wrapped by the fully enclosed electromagnetic shielding unit, and other external interference is isolated during the process of processing the first signal and the second signal.

[0012] Furthermore, the electromagnetic interference minimization processing unit includes resistors R1, R2, R5, R6, and a high-speed comparator U1; the reference voltage Vref is connected to the resistor R2 and then connected to the V- port of the high-speed comparator U1; the V+ port and the V- port of the high-speed comparator U1 are respectively connected in series with resistors R6 and R5 and then grounded; the Vcc port of the high-speed comparator U1 is connected to two parallel capacitors and then grounded; the plasma discharge voltage signal Vin is connected to the resistor R1 and then connected to the V+ port of the high-speed comparator U1.

[0013] Furthermore, the anti-interference hysteresis control unit includes resistors R1, R3, and R7; the plasma discharge voltage signal Vin is connected to the resistor R1 and then connected to the V+ port of the high-speed comparator U1; a resistor R3 is connected in series between the V+ port and the output port of the high-speed comparator U1; the V+ port of the high-speed comparator U1 is connected in series with R7 and then grounded.

[0014] Furthermore, it also includes a signal limiting unit; the signal limiting unit includes a resistor R4 and a bidirectional voltage regulator; after the bidirectional voltage regulator is connected in parallel with the resistor R4, one end is connected to the output end of the high-speed comparator U1, and the other end is grounded.

[0015] Furthermore, the fully enclosed electromagnetic shielding unit includes a full aluminum alloy shell

[0016] Furthermore, the path lengths of the input terminals V+ and V- of the high-speed comparator U1 are equal, that is, the length of the Vin-R1-R6-GND path is equal to the length of the Vref-R2-R5-GND path, and the relationship R1+R6=R2+R5 is satisfied.

[0017] 3. Beneficial effects:

[0018] (1) The scheme proposed in this application uses a commercial high-voltage probe to achieve a movable external trigger, collects the plasma discharge voltage signal for signal processing, can identify various voltage signals at the moment of electrode breakdown and convert them into the trigger signal required by the high-speed camera, and simultaneously shoot the discharge moment frame by frame. This starting scheme does not need to be integrated into any device, can be an independent unit, can match different excitation targets, has high flexibility, and achieves high target compatibility.

[0019] (2) The electromagnetic interference minimization processing unit of the present application ensures that the signal can be transmitted in a differential equal-length symmetrical form, and the equal length of the differential line path is a prerequisite for ensuring that the parasitic parameters in the two lines are equal, the differential signal and the common-mode interference are in phase, and differential operations are performed to filter out most of the common-mode interference.

[0020] (3) This solution achieves a minimized signal layout to achieve consistent impedance matching of the entire circuit. The signal from the source to the path, then to the impedance of the comparator input, and then to the flow path to the ground is extremely tightly arranged at the input port, providing an ideal current flow path through the ground layer, minimizing the impact of parasitic impedance on the circuit board. When there is a signal trace on the ground layer, the return current at high frequency (in the ground layer) flows just below the signal trace, and the reflected signal and the actual signal are layered and circulated, which can reduce the propagation delay of the entire circuit.

[0021] (4) The anti-interference hysteresis control unit in this scheme uses the form of anti-interference positive feedback. When there is stray interference in the signal processed once, it reduces the total hysteresis signal potential VT2, thereby expanding the threshold range and reducing the sensitivity of signal jump.

[0022] In summary, compared with the industrial camera trigger control method, the trigger system of the high-speed camera of this scheme has a strong control ability over noise interference and electromagnetic interference in the high-noise and high-electromagnetic interference scenes of the discharge plasma, and can effectively improve the accuracy of the waveform and the delay of the waveform, so the present invention can be applied to high-interference scenes; compared with the industrial camera trigger control method, the device of the present invention does not require additional triggering equipment such as expensive oscilloscopes, high-resolution signal generators, and difficult technical methods such as photomultiplier tubes or photon detection technology to collect trigger signals to trigger the shutter of the camera; compared with the industrial remote camera trigger control method, the method of the present invention has high compatibility in target matching, and the trigger delay is reduced to the picosecond level, which improves the accuracy of high-speed cameras in capturing spatiotemporal information. Compared with the military camera trigger control method, this scheme can be applied in different scenarios, has high flexibility, simple design method, no need to use communication means for remote control, and can directly observe the results at close range. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A block diagram of an arbitrary pulse compatible high-speed camera synchronization trigger device of the present invention;

[0024] Figure 2 is a block diagram of a high-speed camera triggering system in the present invention;

[0025] Figure 3 The overall circuit structure diagram of the high-speed camera trigger system in the present invention;

[0026] Figure 4 is a processing flow chart of the minimum signal unit signal in the present invention;

[0027] Figure 5 It is a parasitic parameter model diagram of the minimum signal unit transmission line in the present invention;

[0028] Figure 6 This is the waveform diagram of the differential line unequal length signal

[0029] Figure 7 This is the waveform diagram of the differential line equal length signal

[0030] Figure 8 It is the differential current trend diagram of the signal transmission line with equal length of differential line;

[0031] Fig. 9 This is the reflection current trend diagram of the equal-length signal of the differential line;

[0032] Fig.10 is a processing flow chart of the anti-interference hysteresis control unit in the present invention;

[0033] Fig.11 Schematic diagram of Vout positive feedback threshold hysteresis control DETAILED DESCRIPTION

[0034] The present invention will be described in detail below with reference to the accompanying drawings.

[0035] As attached Figure 1 As shown, it is an overall connection diagram of an arbitrary pulse compatible high-speed camera synchronous trigger device of the present application, including an excitation source, a plasma reactor, a high-voltage probe, a compatible trigger device, and a high-speed camera.

[0036] As attached Figure 2 As shown in FIG. 1 , it is a block diagram of the high-speed camera trigger system in the present application. The present system is mainly composed of a minimized signal unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit. The minimized signal unit receives the attenuated voltage signal of the high-voltage probe itself and first processes it to generate a first signal, and then sends the first signal to the anti-interference hysteresis control unit.

[0037] As attached Figure 3 As shown, it is the circuit diagram of the present application; as shown in the figure, the anti-interference hysteresis control unit is provided with a positive feedback trigger reference hysteresis adjustment circuit; the pulse signal is very susceptible to noise interference during the transmission process, which causes the pulse waveform to be distorted, thereby causing the waveform to oscillate irregularly, which will cause the high-speed camera to mistakenly identify the interference signal as a trigger signal, thereby causing the high-speed camera to mistakenly trigger the shooting, and fail to record the physical luminous image at the moment of discharge. This unit adds a positive feedback trigger reference hysteresis adjustment to the signal output port, which can effectively make the pulse signal trigger the high-speed camera to start working first, and in the case that noise interference still exists during the signal transmission process, delay its secondary trigger jump, thereby reducing the trigger sensitivity after the first trigger, and finally output a regular, clean and interference-free pulse signal.

[0038] In order to prevent additional electromagnetic compatibility problems caused by the pulse excitation source itself and the plasma reactor itself during the discharge process, the present application adds a fully enclosed electromagnetic shielding unit to the entire system to eliminate the impact of the electromagnetic interference source and make the output signal waveform stable and continuous.

[0039] As shown in Appendix 4 and 5, in the smallest signal unit, the excessive common-mode interference at the input of the pulse voltage signal source of the plasma discharge reactor will limit the signal integrity of the high-speed circuit. Impedance matching of the transmission path from the signal source to the comparator input is necessary to reduce the propagation delay and waveform integrity of the entire circuit. The source impedance, together with the input stray capacitance, produces an RLC filter, delaying the voltage conversion at the input and reducing the amplitude of the high-frequency signal.

[0040] In high-speed circuits, fast rising and falling switching transients can produce voltage differences between lines, while at DC voltage, the voltage difference is the same. To reduce this effect, a ground plane is used to reduce the voltage potential difference within the circuit board. The advantage of the ground plane is that it minimizes the impact of common-mode interference and reflected current on the circuit board by providing a more ideal current flow path. When there are signal traces on the ground plane, the return current at high frequencies (in the ground plane) tends to flow just below the signal trace, that is, the actual current signal and the noise return signal flow in layers in the ground plane without interfering with each other. Finally, the actual current signal stabilizes the potential at the fixed impedance of the input port through the fixed signal track.

[0041] At the same time, the position and type of the capacitor bypassing the power supply Vcc are also crucial to the high-speed ratio circuit. The capacitor of the comparison circuit is set to buffer the ripple unit of the power supply line. In addition, the capacitor in the power supply ripple buffer unit charges the comparator during the high-frequency switching period, so that the comparator can work stably in the best state. Finally, a relatively clean and good state can be achieved when the signal is input into the system.

[0042] Figure 5 is the parasitic parameter model of the minimum signal unit signal processing circuit, C d V in and V ref The parasitic capacitance between the two paths, R in , R ref is the parasitic resistance of the signal transmission port, L in , L ref is the parasitic inductance of the signal transmission port, L1, L2, L3, L4 are the parasitic inductances on the transmission medium, the path length S1 from Vin to GND and the path length S2 from GND to Vref are equal, ensuring that the signal is transmitted in a differential equal-length symmetrical form.

[0043] If the differential paths are not equal in length, that is, S1≠S2, the signals on the two paths will have a phase difference such as Figure 6 As shown, at t0, V in When the signal is high, V ref There is no corresponding inverting signal. In this way, when performing differential operation, the original high-level signal is mixed with the positive high-level signal and the reverse low-level signal. The original high level of the signal from t0 to t5 is now extended to t0 to t8, and the high-level time becomes longer. In this way, when there is no common-mode interference, the signal has been seriously distorted. Figure 6 -c. After adding common mode interference, due to the phase difference, the common mode interference cannot be eliminated during differential operation, resulting in more serious oscillations such as Figure 6 -d as shown.

[0044] When S1=S2, the signal is V inEnter the transmission to GND and then to V ref , during this period, common mode interference is not considered, only differential signal transmission is used, then V in =-V ref , a regular signal will be received at the signal receiving end V+. When common mode interference ΔV is added EMI When the common mode interference amplitude is in the same direction,

[0045] V in1 The signal is:

[0046] V in1 =V in +△V EMI (1)

[0047] V ref1 The signal is:

[0048] V ref1 =V ref +△V EMI (2)

[0049] The final V+ potential is

[0050] V in1 -V ref1 =V + (3)

[0051] The results are as follows Figure 7 -d shows that after adding common mode interference, V + The signal remains in its original state, and the signal's anti-interference ability is enhanced. Therefore, equal length of differential line paths is a prerequisite for filtering out most common-mode interference.

[0052] In addition, in the process of high-frequency signal transmission, in addition to ensuring that the differential line paths are of equal length, another unavoidable problem is the signal reflection problem, that is, the impedance matching of the transmission line. The signal propagates in the form of electromagnetic waves. When the wave is transmitted from V in When transmitted to the PCB, reflection will occur. Therefore, when there is impedance discontinuity in the signal line transmission path, the signal will be reflected. Signal reflection will cause overshoot, oversag, ringing (signal reflection back and forth) and other problems. Severe overshoot and oversag problems will cause the signal voltage amplitude to exceed the normal power supply range of the device pin, and long-term impact will reduce the service life of the device.

[0053] Figure 8It is the direction of differential current on the transmission line. When the signal is transmitted in the medium, each signal has a reflected signal. An impedance-controlled conductor has a controlled geometric symmetry figure. Part of the symmetry figure is the relationship between the control signal and its reflected signal. If you want the trace on the circuit board to behave as a transmission line, you must control its geometric symmetry, which means controlling the relationship between the signal and its reflected signal. The conventional method is to provide a continuous, relevant, and unbroken reference plane layer under the trace as the place where the reflected current flows. At the same time, the following relationship is satisfied:

[0054] The impedance relationship of the input path is:

[0055] R in +L in =R1+L1+R2+L2 (4)

[0056] The impedance relationship of the output path is:

[0057] R ref +L ref =R2+L4+R5+L3 (5)

[0058] The parasitic inductance Lr of PCB copper is:

[0059]

[0060] Lr—Copper parasitic inductance (nH / in)

[0061] w—Trace width (mil)

[0062] h—Trace height from substrate to reference layer (mil)

[0063] The parasitic inductance relationship of the entire differential path is:

[0064] L in +L ref +L1+L2+L3+L4=L r <L thmin (7)

[0065] Table 1 PCB trace inductance values

[0066]

[0067] The actual parasitic inductance relationship in the PCB is as above. If the delay is less than 1ns, it will not affect the transmission of the circuit signal. That is, when the total parasitic inductance of the line is much smaller than the threshold inductance L thmin The transmission delay will be much less than 1ns. According to the empirical value L thminGenerally, it is 12nH. The copper thickness of this PCB is 1 ounce, the trace length is about 1in, the line width is 45mil, and the trace height from the substrate to the reference layer is 62.99mil. According to Table 1, the parasitic inductance L of this PCB trace is less than 12nH, which satisfies equation (7). Therefore, the parasitic inductance factor can be ignored, and only the matching problem of the line resistance is considered, which satisfies the following relationship:

[0068] Input resistance relationship:

[0069] R in =R1+R6 (8)

[0070] Output resistance relationship:

[0071] R ref =R2+R5 (9)

[0072] The final resistance relationship is:

[0073] R in =R ref (10)

[0074] therefore Figure 8 As shown in the figure, when a signal starts to transmit along the transmission line, the signal is coupled to the reflection path through the distributed capacitance of the transmission line. The arrow indicates its loop. The signal at the bottom of the figure shows the direction of the current if the differential signal is a pulse that quickly returns to 0. The signal is shown in the figure I in The energy shown by the arrows continues to circulate in the loop composed of the routing, reference plane layer and the distributed capacitance between them.

[0075] exist Fig. 9 The arrow in the middle clearly shows the path of the smallest signal unit reflected signal and how the signal is coupled to it. When a signal is transmitted along the trace with a certain transmission time, there is always coupling on the reflection path, but it is not always obvious where the reflection path is or how the coupling occurs. It is generally through air coupling or parasitic capacitance between media.

[0076] When the signal reaches the end of the transmission line, and the transmission line is terminated correctly (such as Fig. 9 As shown in Figure 1, all the energy of the signal is absorbed (heated) in the form of power dissipated in the terminal resistors R5 and R6, so that no remaining energy is transmitted back to the transmission line. Therefore, there is no reflection. This is a characteristic of a properly terminated transmission line.

[0077] If R5 and R6 do not match the characteristic impedance of the transmission line, not all the energy is absorbed by the terminal resistors and the remaining energy can be reflected back to the transmission line. If the transmission line is open or shorted, no energy is dissipated in the resistors (heating) and all the energy is reflected back. If there is some resistance at the end of the transmission line, part of the energy is reflected back.

[0078] Fig.10 The processing flow chart of the anti-interference hysteresis control unit of the present application shows that the input of the comparison circuit has almost no change in the specified offset voltage range. For slow-moving or noisy input signals, when the input signal passes through the switching threshold, the comparator output may result in an undesirable switching state.

[0079] When the voltage signal collected by the high-voltage probe is input into the minimum signal unit, the first signal outputted by the high-voltage probe is outside the preset threshold range, and the second signal processed by the anti-interference hysteresis control unit is outputted normally; when the first signal is less than the threshold range, the hysteresis inside the comparison circuit U1 of the minimum signal unit signal may be insufficient. In order to provide greater noise immunity to the high-speed comparator U1, the total hysteresis signal potential V can be controlled by connecting a small amount of feedback to the positive input. T2 , that is, to control the interval and position of the hysteresis, expand the threshold area, and thus reduce the sensitivity to noise. out A signal limiting circuit is set at the output to stabilize the signal.

[0080] As attached Figure 3 The circuit diagram of the anti-interference hysteresis control unit shown in the figure, when the collected voltage signal is input, as shown in the attached Fig.11 The first signal output by the minimum signal unit shown is within the preset threshold range [V T2 ,V T1 ] In addition, the second signal after the anti-interference hysteresis control unit is processed and the normal output is insufficient for the internal hysteresis of the comparison circuit. For greater noise immunity, the external hysteresis can be increased by connecting a small amount of feedback to the positive input. The total hysteresis signal potential V T2 The transition of is as shown in formula (12) by setting the voltage reference value required for switching the comparison circuit output, that is, controlling the interval and position of the hysteresis, and expanding the threshold area.

[0081]

[0082] By adjusting the input resistor R1 and the feedback resistor R3, V T2 Finally, the output signal is stabilized by setting the signal limiting circuit.

[0083] like Fig.11The figure shows the positive feedback threshold hysteresis control schematic diagram of Vout, that is, the trigger waveform of the camera; Vo is the trigger jump potential, Vi is the transmission signal amplitude, V T1 is the initial trigger threshold, V T2 is the hysteresis trigger threshold, and T is the pulse duration. Fig.11 -a When the interference signal is in the threshold region [V T2 ,V T1 ]outside, Fig.11 -c will cause the signal to trigger falsely; Fig.11 -b expands the threshold range through positive feedback, reducing the sensitivity of signal transition. Fig.11 -d makes the signal output stable.

[0084] Although the present invention has been disclosed as above in terms of preferred embodiments, they are not intended to limit the present invention. Anyone skilled in the art can make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection defined by the claims of this application.

Claims

1. An arbitrary pulse compatible high-speed camera synchronous trigger device, applied to a plasma photoelectric information acquisition system, the system comprising an excitation source, a plasma reactor, an arbitrary pulse compatible high-speed camera synchronous trigger device, a high-voltage probe, and a high-speed camera, characterized in that: The arbitrary pulse compatible high-speed camera synchronous trigger device includes an electromagnetic interference minimization processing unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit; The excitation source is a high-frequency excitation source, which releases pulse excitation to the plasma reactor; the plasma discharge reactor breaks down and discharges under the action of the high-frequency excitation source; the high-voltage probe detects the pulse voltage signal of the plasma discharge reactor from the start to the end of the discharge, and transmits the detected signal to any pulse-compatible high-speed camera synchronization trigger device; The arbitrary pulse compatible high-speed camera synchronous trigger device performs differential anti-interference and hysteresis processing on the received discharge voltage signal to obtain a clean voltage signal; the processed discharge signal is transmitted to the high-speed camera to trigger the high-speed camera to shoot at the corresponding time; The arbitrary pulse compatible high-speed camera synchronous trigger device comprises an electromagnetic interference minimization processing unit, an anti-interference hysteresis control unit, and a fully enclosed electromagnetic shielding unit; the electromagnetic interference minimization processing unit generates a first signal after performing electromagnetic interference minimization processing on the discharge voltage signal of the plasma reactor detected by the high-voltage probe; the first signal is transmitted to the anti-interference hysteresis control unit and then adjusted by positive feedback trigger reference hysteresis to generate a second signal; the first signal and the second signal are wrapped by the fully enclosed electromagnetic shielding unit, and other external interference is isolated during the process of processing the first signal and the second signal; The electromagnetic interference minimization processing unit includes resistors R1, R2, R5, R6, and a high-speed comparator U1; The reference voltage Vref is connected to the resistor R2 and then to the V- port of the high-speed comparator U1; the V+ port and the V- port of the high-speed comparator U1 are connected in series with resistors R6 and R5 respectively and then grounded; the Vcc port of the high-speed comparator U1 is connected to two parallel capacitors and then grounded; The anti-interference hysteresis control unit includes resistors R1, R3, and R7; the plasma discharge voltage signal Vin is connected to the resistor R1 and then to the V+ port of the high-speed comparator U1; a resistor R3 is connected in series between the V+ port and the output port of the high-speed comparator U1; the V+ port of the high-speed comparator U1 is connected in series with R7 and then grounded.

2. The arbitrary pulse compatible high-speed camera synchronous triggering device according to claim 1, characterized in that: It also includes a signal limiting unit; the signal limiting unit includes a resistor R4 and a bidirectional voltage regulator; after the bidirectional voltage regulator is connected in parallel with the resistor R4, one end is connected to the output end of the high-speed comparator U1, and the other end is grounded.

3. The arbitrary pulse compatible high-speed camera synchronous triggering device according to claim 2, characterized in that: The fully enclosed electromagnetic shielding unit comprises a full aluminum alloy shell.

4. The arbitrary pulse compatible high-speed camera synchronous triggering device according to claim 3, characterized in that: The path lengths of the input terminals V+ and V- of the high-speed comparator U1 are equal, that is, the length of the Vin-R1-R6-GND path is equal to the length of the Vref-R2-R5-GND path, and the relationship R1+R6=R2+R5 is satisfied.

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